1 Answer

I can tell you that sometimes "new batteries" fail right out of the box… especially those not purchased from Apple (box store BestBuy had to recall a lot of their Mac laptop batteries as there was a high failure rate).

It' possible that the battery may have damaged your connector or the SMC… but first go over the connector again. Ensure that is is not damaged (use a magnifier to look) that when you reconnect the battery the magsafe is also unplugged, and that the connection is square and fully snapped in.

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